Investigation on Erosion Resistance of WC-Co-Cr Coatings

The erosion behavior of three high velocity oxy-fuel/air-fuel (HVOF/HVAF) sprayed WC-Co-Cr coatings has been investigated using Al2O3 as erodent at impingement angles of 15° and 90° and impact velocity of 30 m/s. The results indicated that the mixed removal of Co-Cr binder and WC cuboids, plastic deformation, fracture of lips and coatings spallation were main erosion mechanisms. The erosion resistance of coatings at different erosion conditions was very much dependent on the microstructure of coatings. To sum up, the coatings with denser and more homogeneous microstructure exhibited better erosion resistance